coli BL21DE3/pBJN406 grown on TSA plates in the presence of 0.5, 1.5, 2.5 and 3.5 mM of agents 1 and 2, respectively. In the experiments presented by M and N panels the E. coli BL21DE3/pBJN406 strain was grown in the presence of 3.5 mM of pilicides. The selleck chemicals Figure presents representative results obtained from
three independent experiments. Each experiment was composed from the four-fold repetition for each used bacterial preparation. The bacterial adherence to 40 CHO cells was determined for each repetition. Presented Alvocidib in the figure pilicides 1 and 2 are the literature agents which, at a 3.5 mM concentration, inhibit the assembly of FGS type 1 and P pili. Pilicides block Dr fimbriae-dependent bacterial adherence At the first stage, we determined
the adherence of bacteria cultivated on TSA plates in the presence of 0.5, 1.5, 2.5 and 3.5 mM of pilicides 1 and 2 to the CHO cells transfected with plasmid encoding DAF receptor protein recognized by Dr fimbriae. The process of bacteria attachment was visualized by means of Giemsa staining. In the case of strain BL21DE3/pBJN406 cultivated without pilicide (positive control), we observed a high level of bacteria attachment to the CHO-DAF+ cells related to the undisturbed production of Dr fimbriae (Figure 1I). The adherence of positive control is set as 100% ±12 and the observed adherences of all other used bacterial preparations are expressed as the percentage of mean value of adherence present relative to control. The addition of 3.5 mM
pilicide to the bacterial growth media resulted in a very high reduction check details in the bacterial adhesion properties: for pilicide 2, only a few bacterial cells were visible as attached, corresponding to the relative bacterial adherence of 13% ±3 (Figure 1B) and for pilicide 1 resulted in a slightly lower inhibition of bacterial attachment, corresponding to the relative adherence of 25% ±7 (Figure 1A). E. coli BL21DE3/pBJN406 bacterial strains cultivated in the presence of 0.5, 1.5 and 2.5 mM of pilicides 1 and 2 showed dose dependent relative adherence of: 90% ±3, 60% ±5 and 32% ±6 for pilicide 1 and 92% ±8, 42% ±7 and 21% ±9 for pilicide 2, respectively (Figure 1 G,E,C and H,F,D). In order to confirm that the bacterial adherence is dependent on the specific interactions between the DraE MYO10 fimbrial subunits and DAF, we used as the control non-transfected CHO cells, which do not express DAF molecules naturally. The relative adherence of Dr-fimbriated BL21DE3/pBJN406 positive control (Figure 1J), non-fimbriated BL21DE3/pACYC184 negative control (Figure 1L) and BL21DE3/pBJN406 strain grown in the presence of 3.5 mM of pilicide 1 or 2 (Figure 1M and N) to the CHO-DAF- cells for all experiments was of 3-6% ± 1–2. The similar value of relative adherence of 5% ±6 was determined for binding of non-fimbriated BL21DE3/pACYC184 negative control strain to CHO-DAF+ cells.